Gilbert de Clare, 7th Earl of Gloucester

Gilbert de Clare, 7th Earl of Gloucester (2 September 1243-7 December 1295) was Earl of Hertford and Gloucester from 1262 to 1295, succeeding Richard de Clare and preceding Gilbert de Clare.

Biography
Gilbert de Clare was born in Christchurch, Hampshire, England in 1243, the son of Richard de Clare, 6th Earl of Gloucester and Maud de Lacy. In 1262, he inherited the titles of Earl of Hertford and Gloucester and Lord of Glamorgan, and he was responsible for the 1264 massacre of the Jews at Canterbury. De Clare and Simon de Montfort were denounced as traitors by King Henry III of England, and he commanded the central division of the Baronial army at the Battle of Lewes during the Second Barons' War. In 1264, De Clare was excommunicated by Pope Clement IV, and he decided to betray De Montfort and join the King's forces. He commanded the second division of the royal army at the Battle of Evesham, and he was rewarded for his service with the castle and title of Abergavenny and honor and castle of Brecknock. In 1272, he swore fealty to King Edward I of England, and he also proclaimed peace to all (both Christians and Jews) in London the next day. In 1282, he commanded the southern army invading Wales, but his defeat at Llandeilo Fawr led to William de Valence, 1st Earl of Pembroke replacing him as commander. In 1291, he waged a private war against Humphrey de Bohun, 3rd Earl of Hereford, leading to his fining and imprisonment. He died at Monmouth Castle in 1295.